


Long Tails and Tidepools

by swiftishere



Series: MSA AU Bin [7]
Category: Mystery Skulls Animated
Genre: Dehydration/Heat Exhaustion, Gen, MerMay 2020, Mermaid/siren AU, Music, Other Additional Tags to Be Added, Rescue, Siren!Arthur (Mystery Skulls Animated), Vaguely at least
Language: English
Status: Completed
Published: 2020-05-05
Updated: 2020-05-16
Packaged: 2021-03-03 04:35:00
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 3,838
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24019108
Author URL: https://archiveofourown.org/users/swiftishere/pseuds/swiftishere
Summary: There are plenty of warnings people share about the ocean. More mundane concerns speak of the dangerous riptides, freezing water, and rocks that threaten to dash apart ship and body alike. Other, more esoteric warnings are of the sirens that are rumored to live beneath the waves, waiting with voices and sharp gazes to steal away any who venture beyond the relative safety of the cliffs above the beach.But the low tide today brings with it the opportunity to see things that the water normally hides, and despite the warnings, Lewis can't help but be intrigued. So he sets off for a short expedition, to see what lies beyond the tide line.
Relationships: Arthur & Lewis (Mystery Skulls Animated)
Series: MSA AU Bin [7]
Series URL: https://archiveofourown.org/series/1942603
Comments: 17
Kudos: 98





	1. Chapter 1

**Author's Note:**

> this time for sure, gang. for pretty sure anyway. mmmmaybe i'll continue this, who knows. 
> 
> [over here](https://nemesis-is-my-middle-name.tumblr.com/post/617075913622962176/not-that-im-officially-doing-mermay-or-anything) is a depiction of siren!arthur! obviously in a different setting than here, but if you're curious about what he looks like, there it is!

“It’s a negative tide, they’ll all be way out at sea,” Lewis said, waving a hand. “And I won’t go that far out anyway.”

“It’s still dangerous.” His mother turned to frown at him, not looking at the pot she was setting down in the sink. "You know how deep some of the pools out there can get. What if you slip and-"

"I'll be _careful_. I'll stay away from anything that looks too deep. And I'll be wearing my boots – the ones with the grips on them. I just want to go out and explore a little. Vivi says last time this happened, she saw an octopus!"

" _Vivi_ also fell and cut her leg open!" his father called from the other room. "I don't want to see you copying _that!"_

"I won't! I'm not going out on the rocks or anything like that – just walking around.” While he wouldn’t have admitted it, he was a _little_ worried, and his parents weren’t helping with that, but he also really wanted to do this. Vivi hadn’t stopped talking about how cool it had been last time, and it had been on his to-do list ever since, and he’d been planning it for _this_ long and he was _not_ just going to give up.

His mother pursed her lips and frowned at him for a moment. "I trust you to be careful. But if _anything_ happens..."

"The tide's due to start coming in a little after sundown – if I'm not back by then..."

The defined end point seemed to help, and she sighed, shaking her head a bit. "All right."

"Can I go too?" Belle had materialized at their feet, making Lewis jump.

"No." Their mother's response was instant. "It's too dangerous, sweetie."

"But you're letting Lew go!" Cayenne chimed in. "I wanna see an ockapus!"

"Octopus," he corrected. "And Mom's right. You're too little. What if you fall in the water somewhere, huh?" He knelt down to his sisters' level. "I'm bringing my camera, and if I find anything interesting, I'll take lots of pictures, okay? It'll be like you were actually there."

Belle, at least, recognized that she'd been outvoted. "Okay... be careful!"

"Of course!" He picked up both girls in a hug, and then stood back up. "I won't be long."

* * *

Despite his initial anxieties, Lewis found himself enjoying this even more than he’d thought he would. It was a nice day out, the warmth from the sun overhead balancing out against – maybe even overpowering a little – the cool breeze drifting in off the ocean. He hadn’t really _seen_ anything interesting, but he also hadn’t gone too far out yet. He’d only just taken the turn from walking on what was normally the shoreline, out into the parts of the beach that were normally covered in water.

Already he was seeing anemones, sea urchins, a plethora of mussels and snails, and even a few crabs that quickly darted into cracks in the rocks when he got close. He’d had to stop taking photos of everything that caught his eye, because there was just _so much_ to look at.

Still no sign of any fish or the fabled octopus, though, so he kept walking out. The rocks were still slick out here, the tide having left this place fairly recently.

Something that was little more than a spot of color caught his eye. Bright orange, too far away to make out clearly.

"Octopus," he murmured under his breath as he drew closer, picking up the camera bag at his waist with one hand, "please, octopus.”

But it was too big to be an octopus, he realized as he drew closer. And then, suddenly enough to steal his breath away, he recognized what it _actually_ was.

A _siren_ was half-curled up in a small tidepool. His long tail was coiled and piled up in what little space there was in the water, submerged alongside only half of his torso – the other half was left above the water, arms folded on the rocks to create a resting space for his head. Long orange hair obscured any view of his face. Lewis's first instinct was to run, but he froze instead, wary of falling on what was now slick rock underfoot. He found himself watching, with some degree of both fear and fascination, the gills he could see lining the siren's chest, as they slowly opened and closed.

The arms twitched and Lewis reflexively took a step back, heart jumping when his shoe skidded a little. He watched with his heart now in his throat as the siren stirred from his sleep, pushing himself up onto his elbows – he only now noticed the diamond-shaped patches of black scales on them.

The siren's movements were slow, and almost jerky. He blinked and then shut his eyes, shaking his head a little as he did and swallowing harshly. Leaning more heavily on one arm, he half-covered his face with the other, shielding his now closed eyes from the sun. And then he shifted further, putting his hands down on the rock to push himself up more, and Lewis waited for him to turn and look at him.

Instead of that, and instead of showing any sign that he'd noticed him, he slipped backwards into the water – Lewis watched his still-coiled tail shift sideways and out of the water to make room, as he almost entirely submerged the human upper half in the pool. After a moment, and now with slightly shaking arms, he pulled himself back up out of the pool entirely.

It took Lewis a moment to figure out what he did next – it looked like he was attempting to reach towards the cliff not far away. He quickly recognized the movements as him trying to climb out of the pool, but it seemed he couldn’t get the grip needed to actually _move_. His tail uncurled somewhat and pressed against the rock, trying to give him a little more force, but there wasn’t enough to brace against and it just slid backwards. That in turn sent him sprawling, which earned a sympathetic wince from Lewis – that would probably result in some nasty scrapes.

He kept trying, but the motions were increasingly desperate and… weaker. Soon he couldn’t do much more than hold himself up with one arm and reach forwards with the other. His hair had moved enough to show his eyes, staring desperately forward at the water glimmering just out of reach, and… was he _crying?_

Whatever fear Lewis had of the siren was entirely lost by now. Now he just felt _bad_ – how long had it been since the tide had gone out? He must have been stranded here since then – he was probably almost out of _oxygen_ in that tiny pool, wasn't he? _And_ dehydrated and overheated, too, being trapped in direct sunlight for so long- there probably wasn't much, if anything, he could do to him, but... he'd probably be _dead_ pretty soon if he stayed out here much longer, from one thing or another.

He must have given up on climbing out, because he slid backwards to his original half-submerged position again, only now shaking with his hands over his head. He shifted again with a soft, keening whine, and the end of his tail twitched, in what he identified as a vain attempt to find a place to dip it underwater.

Wasn't there _something_ he could do to help him? If he could just get him back into the ocean- the cliff really wasn't too far away, and that was a sheer drop into the water.

The siren scarcely seemed to notice as he drew closer. Up until he gently touched his back, that is- and then he jumped, turning and shrinking as best he could against the far side of the tidepool. His half-bared teeth were _sharp_ , Lewis noticed, warning rows of daggers hidden in his mouth, and he started to rethink this-

-but almost immediately the warning snarl vanished from his face as his head dipped forward, and he only narrowly avoided just collapsing into the water by catching himself with his hands. Eyes closed again, he just laid in the pool, his shoulders heaving and gills doing little more than twitching without any real rhythm. Whatever threat he’d held before was lost again – he really was just trapped and afraid. Lewis couldn’t help but start murmuring reassurances as he drew closer.

"I'm not going to hurt you. You'll be okay, alright?” He placed a hand on the siren’s shoulder, noting how dry and cracked the skin felt, and he was sort of expecting it when he flinched, but at least he didn’t dart away again. “You’re gonna be fine, just trust me." He turned him into a more upright position- and suddenly found himself looking right into his eyes.

They were completely orange, except for the pupils larger than a human’s, and his expression was almost entirely vacant. Lewis took a deep breath and forced himself to look away – it was harder than it should have been, there was _something_ about that gaze, even unfocused as it was.

It was tricky to maneuver the siren into a position where he could easily pick him up, and he had to struggle a bit with the tail. Eventually he ended up with one arm around the siren's lower back, and the other under the main section of the coiled-up tail. "Just- a little ways- and then you'll be back in the ocean, I promise."

He was grateful all over again for his sturdy gripped boots as he lifted the siren up, somehow managing not to fall backwards in the process. He was _heavy_. Which he'd been expecting, but it didn't make it any less difficult as he stumbled towards the cliff, struggling to strike a balance between being careful – too fast and he'd probably trip – and going quickly, because there was a very real chance the siren he was carrying would asphyxiate if he was out of the water for too long.

At least there wasn’t too much of a drop into the water. He practically dropped the siren, falling to his knees in the process and probably earning himself a few good scrapes, and getting a splash that managed to soak most of his shirt. He managed to catch and hold on to the siren’s arms, not wanting to let go before he was sure he could actually swim.

There was a long moment where he waited with bated breath, almost worried that he _had_ taken too long and he was dead, or too far gone to wake back up. But then he watched as his gills started to open and close more fully, in an actual breathing-like rhythm, and his tail actually started to move slightly instead of just drifting with the current.

Finally his eyes actually opened, and his head lifted up, and Lewis found himself caught by that orange gaze once more. His eyes were half-lidded and only hazily turned on him, blinking frequently despite being faced away from the sun.

Lewis wasn’t quite sure what to do next. He was still kneeling on the rocks, and the chill from the water said he should be shivering, but he wasn’t even doing that. He just kept his loose grip on the siren’s arms and staring into his increasingly wakeful and focused eyes.

And then the siren’s tail swished more forcefully, and before he really knew what was going on the siren had twisted out of his hands, deftly turned and dove into the water, and in a flash had vanished.

Lewis blinked into the light of the setting sun, trying to watch the trail of orange as it disappeared out to sea. That was what prompted him to realize that the sun was setting. Shit, he had to get _going_.

He still couldn’t help but glance over his shoulder one more time as he headed back towards the shore, despite not being able to see the ocean anymore.

* * *

He was still thinking about the siren towards the end of the walk back to his house, but by that point, he was sweaty and his clothes were somehow _still_ wet and he was _tired_ and mostly, he just wanted to take a shower and maybe go straight to bed.

Which of course meant he opened the door and was immediately beset by both his parents.

“You cut it awfully close- _why are you soaking wet?_ ” his father started.

“Your legs!” was the first thing his mother noticed. “Did you slip? Are you hurt anywhere else?”

He took a deep breath and tried to think. “I… fell… into… a tidepool. That’s all.” He just hoped they’d take his slow, deliberate speech as drawn-out certainty, and not him scrambling to think of a good lie. “I, uh, was leaning over to look at… this thing… and I slipped. It was only three feet deep, um, or so.” How deep was three feet? That was a reasonable number, right? “I’m fine. Just tired and wet.”

“I knew that this was a bad idea.” Now his mother was giving him that pursed-lips frown of hers, and _damnit_ he didn’t want to do this.

“It’s fine! It… was cool, really. Aside from that one part where I fell. I got some cool pictures, I’ll show you, just… uh, after I take a shower.”

“You’re _sure_ you’re not hurt anywhere else?” His dad was inspecting his arm now.

“ _Yes_. I told you, I’m _fine_. I’ll tell you all about it later.” Hopefully between now and then he’d have enough time to come up with a believable lie. The ‘fell in a tidepool’ story was solid, he was pretty sure.

They both backed up at that, and he barely suppressed a sigh of relief.

“We _are_ talking about this later,” was called to his back as he left.

“I promise! Shower, girls to bed, and then we’ll talk.”

He was going to be _so_ tired by then.


	2. Salvage

**Summary for the Chapter:**

> The day after.

It wasn't until the latch of the screen door clicked firmly behind him that Lewis allowed himself to exhale and relax, leaning on the wooden post next to the door.

He didn't linger long, though, before he pushed off the pole and started walking. Soon he was out the gate, and then towards the cliff road.

The sun was once again in its midday position high in the sky, and a cool breeze was stirring up, gaining strength as he picked his way down the rocky path. It had been a few days since he last followed this trail. He knew he shouldn't be pushing his luck with a second trip, even if he had managed to keep his secret for now, and _technically_ , he really wasn't supposed to be going out here, but he couldn't help it. He hadn't been able to stop thinking about the siren since he first got back, and he _had_ to go again, even if it was just to confirm with himself that it was gone.

The beach, once he got down to it, was as bright as he remembered. Clouds were gathering in the sky, but far off and sparse enough that he wasn't too worried about them. He'd gone down at low tide, so he could actually see some sand and solid surfaces as he walked along the bottom of the cliffs.

He walked slowly, with his gaze mostly directed off towards the sea. He was still paying enough attention to what was in front of him, though, that he noticed the light-colored piece of _something_ standing out against the sand.

It looked at first glance to be a discarded fishing net, but he quickly realized that it was far too fine, made of something thinner than – but still as strong as – the rope the nets were woven from. And it _glittered_ , he noticed. When he knelt to investigate, it was easy to see the source; the net was dotted with small gemstones and gold coins, deftly woven into the mystery twine. It's _full_ of treasures, he realizes, picking it up and unfolding it.

A tiny statuette catches his eye, something made of what looks to be blown glass. It's a mermaid sculpted to be perching on a rock, stretching, face turned to the sky. The expression is impossible to make out – if it once had that level of detail, the tide has long since washed it away – but the pose speaks of yearning, of some deep longing for whatever is above. Its tail is studded with tiny multicolored gemstones that must be meant to mimic scales, that glimmer and reflect the sunlight in a tiny rainbow.

He raises his head and looks around, searching for any sign of another person on the beach. _Surely_ nobody would just _leave_ this, right? Someone _had_ to be looking for it, unless-

_Oh._

His face turns out towards the sea, now scanning for any glimmer of orange, the flick of a tail fin... there's nothing to be seen – how long ago did he leave this? – but he's _sure_.

That discovery presents him with a new problem, though.

_You saved his life,_ half of his mind says. _You deserve a reward._

_I hardly did anything! Just walked ten feet,_ the other half argues, _I don't deserve_ **_this_ **_much. How much must all these treasures be worth? I can't take_ **_all_ **_of it._

_It's a gift, freely given. Taking it is the whole point. How would you even go about returning it, anyway? Just toss it back into the sea and hope?_

He looks back up at the ocean – and stops.

Locking eyes with him is a familiar face, pale skin still turned red by the sun and hair that rings around him in the water and long, pointed fins in place of ears. Far behind him there's the tip of an orange tail with a sharply angular fin, swaying gently back and forth. And those _eyes_ , orange and wide and sharp, so much that they almost pin him in place.

He’s not sure how long he sits there, staring, before he blinks and the spell seems to break.

“I-” he starts, holding out the net in one hand and the statuette, now separate, in the other, “I can’t...”

But the siren quickly puts up a hand, as though pushing his back.

He lowers his hands, blinking. After another moment, he says, “thank you. I... _thank you_.”

At that, maybe understanding him or maybe just reacting to the gesture of him keeping the net, the siren offers a wide grin and _god_ , there are those _teeth_ again, unnervingly sharp and glinting with reflected sunlight from the sea.

He can’t help but try to smile back, though it’s halfhearted.

* * *

The path up the cliff flies by much quicker than it seemed to going down – or maybe he's just hurrying, half because of the setting sun and half because of the net in his arms. There's still the lingering half-fear that he _can't_ have this, that the siren will come and take it back if he doesn't hurry away, and he knows that's mostly irrational but it still makes his feet move quicker up the rocky slope.

And then there's also the tide coming in behind him, quicker than he would have liked under _any_ circumstances, but _especially_ right now. The water laps almost at his heels as he scrambles up the path, the sound making him paranoid and watchful for suddenly slick rocks to trip on. By the time he makes it to the top, he's convinced himself that he's only a few inches behind looming disaster.

He slips into the house and slams the door probably harder than he really needed to, causing everyone inside to look up.

"Lewis, where have you _been_?" his mother starts, standing up – alongside the entire rest of his family, who all just _had_ to be waiting in the living room, _huh?_

"Okay, I went down to the ocean again. _But_ -" he cuts them off mid-outcry- " _Look what I found!_ " And he holds up the net, letting the gems and gold catch the dimming sunlight.

Everyone's eyes go wide; even Paprika in her father's arms stops and stares with an open mouth.

"Where did you _get_ that?" His mom is the first to break the silence. Belle follows up with, "Whose is it?"

"I found it. I think... someone must have lost it."

"We need to take that back into town. Someone will be looking for-"

" _No!_ " _This is my_ **_gift_** _!_ a small part of him shouts reflexively, half angry and half alarmed. "I- listen, whoever this belonged to, I don't... think they're around anymore. Not to look for it, at least."

His parents seem to infer enough from that to drop the subject. His father finishes with, "if _anyone_ hears anything about it- we're going to give it right back."

And then everyone gives in and starts ooh- and aah-ing over the net like he had, and eventually he relinquishes it to his parents for them to look after, for the time being.

His fingers brush the statuette in his pocket, and he finds himself glancing over his shoulder as he goes up the stairs. He's fine with his family investigating the rest of the net, but he wants to keep the mermaid to himself. For now, at least.

* * *

He slides the window open, pauses for a moment to inhale the lightly salty air, and then climbs out and onto the roof.

It's been a while since he was up here, and probably even longer since he took out the instrument currently in his hands. And it shows – the violin is in dire need of tuning, and he spends a good fifteen minutes fiddling with everything and getting it roughly in tune.

In theory, he and the siren are even now. He saved his life, and in return he got a near-priceless collection of artifacts from the sea. But he still doesn't _feel_ that, not when the imprint of those eyes are still burned into his mind. So he came up with a solution. He knows he's still good – like, _really_ good – at the violin, and he knows that music is _super_ important to sirens. He just hopes _~~his friend~~_ the siren will recognize it's for him.

He sets the bow in the crook of his neck, draws back the bow, and begins to play.

With how long it's been since he played, he'd almost forgotten how _good_ it feels. The only thing he has to focus on are the strings and the notes, the instrument singing out over the wind and the waves. He can't tell how long he sits up there, cross-legged on the roof, just playing from the heart.

His eyes might be playing tricks on him, but he almost believes he sees a small glitter of orange in the moonlight when he finishes playing and opens his eyes – only for a moment, before it dives out of sight again.


End file.
